Re: [PATCH] ARM: tegra: cpuidle: implement cpuidle_state.enter_freeze()

2015-05-15 Thread Russell King - ARM Linux
On Fri, May 15, 2015 at 11:03:35AM +0200, Tomeu Vizoso wrote: > I have been looking and asking around, and seems like we should > actually leave FIQs enabled when the tick is frozen and only disable > them within enter_freeze. > > My understanding is that FIQ handlers are extremely limited in what

Re: [PATCH] ARM: tegra: cpuidle: implement cpuidle_state.enter_freeze()

2015-05-15 Thread Tomeu Vizoso
On 17 April 2015 at 16:08, Lorenzo Pieralisi wrote: > On Thu, Apr 16, 2015 at 03:37:19PM +0100, Tomeu Vizoso wrote: > > [...] > >> >> I don't know what FIQs are. :-) >> > >> > In short, fast IRQs, it is a separate IRQ line handled as a separate >> > exception source with some private (banked) regi

Re: [PATCH] ARM: tegra: cpuidle: implement cpuidle_state.enter_freeze()

2015-04-28 Thread Tomeu Vizoso
On 17 April 2015 at 17:02, Tomeu Vizoso wrote: > On 17 April 2015 at 16:08, Lorenzo Pieralisi > wrote: >> On Thu, Apr 16, 2015 at 03:37:19PM +0100, Tomeu Vizoso wrote: >> >> [...] >> >>> >> I don't know what FIQs are. :-) >>> > >>> > In short, fast IRQs, it is a separate IRQ line handled as a se

Re: [PATCH] ARM: tegra: cpuidle: implement cpuidle_state.enter_freeze()

2015-04-17 Thread Tomeu Vizoso
On 17 April 2015 at 16:08, Lorenzo Pieralisi wrote: > On Thu, Apr 16, 2015 at 03:37:19PM +0100, Tomeu Vizoso wrote: > > [...] > >> >> I don't know what FIQs are. :-) >> > >> > In short, fast IRQs, it is a separate IRQ line handled as a separate >> > exception source with some private (banked) regi

Re: [PATCH] ARM: tegra: cpuidle: implement cpuidle_state.enter_freeze()

2015-04-17 Thread Lorenzo Pieralisi
On Thu, Apr 16, 2015 at 03:37:19PM +0100, Tomeu Vizoso wrote: [...] > >> I don't know what FIQs are. :-) > > > > In short, fast IRQs, it is a separate IRQ line handled as a separate > > exception source with some private (banked) registers that minimize > > registers > > saving/restoring. They a

Re: [PATCH] ARM: tegra: cpuidle: implement cpuidle_state.enter_freeze()

2015-04-16 Thread Tomeu Vizoso
On 10 April 2015 at 12:08, Lorenzo Pieralisi wrote: > On Thu, Apr 09, 2015 at 10:19:59PM +0100, Rafael J. Wysocki wrote: >> On Thursday, April 09, 2015 11:18:25 AM Tomeu Vizoso wrote: >> > On 04/08/2015 01:55 PM, Lorenzo Pieralisi wrote: >> > > On Wed, Apr 08, 2015 at 11:54:38AM +0100, Tomeu Vizos

Re: [PATCH] ARM: tegra: cpuidle: implement cpuidle_state.enter_freeze()

2015-04-09 Thread Rafael J. Wysocki
On Thursday, April 09, 2015 11:18:25 AM Tomeu Vizoso wrote: > On 04/08/2015 01:55 PM, Lorenzo Pieralisi wrote: > > On Wed, Apr 08, 2015 at 11:54:38AM +0100, Tomeu Vizoso wrote: > >> This callback is expected to do the same as enter() only that all > >> non-wakeup IRQs are expected to be disabled. >

Re: [PATCH] ARM: tegra: cpuidle: implement cpuidle_state.enter_freeze()

2015-04-09 Thread Tomeu Vizoso
On 04/08/2015 01:55 PM, Lorenzo Pieralisi wrote: > On Wed, Apr 08, 2015 at 11:54:38AM +0100, Tomeu Vizoso wrote: >> This callback is expected to do the same as enter() only that all >> non-wakeup IRQs are expected to be disabled. > > This is not true or at least it is misworded. The enter_freeze()

Re: [PATCH] ARM: tegra: cpuidle: implement cpuidle_state.enter_freeze()

2015-04-08 Thread Lorenzo Pieralisi
On Wed, Apr 08, 2015 at 11:54:38AM +0100, Tomeu Vizoso wrote: > This callback is expected to do the same as enter() only that all > non-wakeup IRQs are expected to be disabled. This is not true or at least it is misworded. The enter_freeze() function is expected to return from the state with IRQs

[PATCH] ARM: tegra: cpuidle: implement cpuidle_state.enter_freeze()

2015-04-08 Thread Tomeu Vizoso
This callback is expected to do the same as enter() only that all non-wakeup IRQs are expected to be disabled. It will be called when the system goes to suspend-to-idle and will reduce power usage because CPUs won't be awaken for unnecessary IRQs. Signed-off-by: Tomeu Vizoso Cc: Rafael J. Wysock